Tuesday, April 4, 2017

Appropriate Application for Pressure Regulator Valve and Back Pressure Regulator

pilot operated sliding gate pressure regulator
Pilot Operated Sliding Gate
Pressure Regulator
Courtesy Jordan Valve
Fluids move throughout processes, driven by pressure produced with mechanical or naturally occurring means. In many cases the pressure generated by the driving source is substantially greater than what may be desired at particular process steps. In other cases, the operation may dictate that a minimum pressure be maintained within a portion of the process train. Both cases are handled by the appropriate valve type, designed specifically to regulate pressure.

A pressure regulating valve is a normally open valve that employs mechanical means, positioning itself to maintain the outlet pressure set on the valve. Generally, this type of valve has a spring that provides a countervailing force to the inlet pressure on the valve mechanism. An adjustment bolt regulates the force produced by the spring upon the mechanism, creating an equilibrium point that provides flow through the valve needed to produce the set outlet pressure. A typical application for a pressure regulator is to reduce upstream or inlet pressure to a level appropriate for downstream processing equipment.

self operated pressure regulator valve
Self-operated Pressure Regulator
Courtesy Jordan Valve

Back pressure valves are normally closed, operating in a logically reversed fashion to pressure regulators. Where pressure regulators control outlet pressure, a back pressure valve is intended to maintain inlet pressure. Similar internals are present in the back pressure valve, with the valve action reversed when compared to a pressure regulator. An inlet pressure reduction in the back pressure valve will cause the valve to begin closing, restricting flow and increasing the inlet pressure. A representative application for a back pressure valve is a multi-port spray station. The back pressure valve will work to maintain a constant setpoint pressure to all the spray nozzles, regardless of how many may be open at a particular time.

Both of these valve types are available in an extensive array of sizes, capacities, pressure ranges, and materials of construction to accommodate every process requirement. Share your fluid control challenges with a process control specialist. Combining your process knowledge with their product application expertise will produce effective solutions.